1 The questionnaire was also pilot tested in the target population. We compiled a pooled items’ list based on the research questions and objectives of the prospective cohort study. A systematic search of the MEDLINE database for published travel medicine surveys was conducted using the terms “validation studies,”“questionnaires,”“travel health,” and “survey methods. We formed a panel of four infectious diseases physicians Crizotinib purchase and two epidemiologists with experience in epidemiological studies involving travelers. The pooled items’ list from the literature review was presented to the panel to assess the relevance of the items to the study’s research questions. Two separate questionnaires

(version 1) were PARP inhibitor designed from selected items: the first to be completed by travelers before travel (pre-travel) and the second after returning from travel (post-travel).

An initial cognitive review of the questionnaires was performed by the expert panel. The questionnaire appraisal system (QAS-99)7,8 was used to identify potential problems with each item, and then each item was reviewed and coded under the following QAS-99 categories: (1) reading; (2) instructions; (3) clarity; (4) assumptions; (5) knowledge or memory; (6) sensitivity or bias; (7) response; and (8) other. Items were then reviewed and revised until there was consensus within the expert panel. The expert panel determined the cognitive tasks required and the likely limitations

in completing the items in the questionnaires: (1) free recall (short-term or long-term recall); (2) frequency judgments; and (3) magnitude estimation.9,10 The questionnaires were then redrafted (version 2) to minimize the difficulties encountered in performing these tasks. The study was approved by the Melbourne Health Human and Research Ethics Committee (2007.112) before the pilot test. A pilot study of the pre- and post-travel questionnaires Interleukin-3 receptor (version 2) was conducted with travelers over a 3-month period. The questionnaires were self-administered paper surveys; participants were observed for any difficulties responding to items. Semi-structured interviews and feedback forms were used to identify unclear items requiring interpretation and to generate new items based on traveler responses. A review of the findings from the pilot period was performed prior to a further redrafting of the questionnaires. Cognitive interviews were performed with 10 participants using the redrafted post-travel questionnaire (version 3). Cognitive interviews were conducted to (1) identify comprehension problems; (2) determine strategies used by travelers to recall travel; (3) assess how travel-related health episodes were recalled, whether providing memory cues was useful, and how confident travelers were of their recall of events; and (4) revise areas in the questionnaire to improve response accuracy.